Response to Press Perturbation

Construct a function to calculate response to perturbation.

press.impact(edges, perturb, monitor = NULL)

Arguments

edges	an edge list.
perturb	a named vector that indicates which nodes were perturbed and the relative magnitude of the perturbation.
monitor	n named vector that indicates the subset of nodes to monitor.

Value

Returns a function that when applied to a community matrix calculates the response to a press perturbation.

Details

Given the an edge list that specifies a directed graph, a set of nodes to perturb and a set of nodes to monitor, press.impact constructs a function of a single argument W that determines the response of the monitored nodes to the perturbation for a simulated community matrix W.

Examples

set.seed(32)
## Sample model
edges <- parse.digraph(c(
  "E *-> D",
  "D *-> C",
  "C -> E",
  "E *-> B",
  "B *-> A",
  "A -> E",
  "D --> B"))
edges <- enforce.limitation(edges)
s <- community.sampler(edges)
s$select(0.5)
## Perturb D, monitor C
f <- press.impact(edges,perturb=c(D=1),monitor=c(C=0))
W <- s$community()
f(W)
#> [1] -0.1423594
W <- s$community()
f(W)
#> [1] 0.3849461
## Perturb D, monitor all
f <- press.impact(edges,perturb=c(D=1))
W <- s$community()
f(W)
#> [1] -6.294866 -7.373123 -8.269788 -6.722383 -3.906486
W <- s$community()
f(W)
#> [1] 3.2166319 1.8985287 2.8477769 0.9746708 2.5440113